I think what should happen is that BMW must start scalping new bikes for spares instead of selling them, at least there will be happy customers. I would rather have my name on a waiting list for a new bike than on a parts waiting list.
Easy to say, but I am not at all sure, you would sit there waiting patiently while your bike is being scalped for parts for my bike. I think, from a business point of view, BMW will agree with me and get your bike to you soonest, before you buy a KTM or Yamaha. Me, I am captive and have to wait.